Traveller assembly cross arm bracket



Nov. 22, 1 A. K. JORDAN ETAL 3,

TRAVELLER ASSEMBLY CROSS ARM BRACKET 5 Sheets-Sheet 1 Filed April 5, 1965 Nov. 22, 1966 A. K. JORDAN ETAL 3,286,968

TRAVELLER ASSEMBLY CROSS ARM BRACKET Filed April 5, 1965 5 SheetsSheet 2 N 1966 A. K. JORDAN ETAL TRAVELLER ASSEMBLY CROSS ARM BRACKET 5 Sheets$heet 5 Filed April 5. 1965 United States Patent 9 5, 8 3 Claims. (Cl. 248226) The present invention relates to a traveller assembly or pulley block used for the stringing of electric conductors on poles or towers.

Electric transmission lines are Conveniently constructed using a series of towers or poles carrying insulators for supporting the conductors and insulating them from the towers. The conductors need to be carefully handled during the erection of the line to prevent kinking or scratching of the surfaces.

The technique used for stringing electric conductors in present is to mount a traveller on each of the poles, to pass a pulling cable over or through the series of travellers, and to draw the pulling cable through the travellers by means of a winch. A running board is attached to the end of the pulling cable, and the electrical conductors to be strung are in turn attached to the running board to trail rearwardly therefrom while being maintain in tension during the stringing operation by braked pay-out drums.

Sometimes it is desired to string new conductors on poles or towers that already carry one or more conductors in service. This requirement arises more often in lower voltage lines using wooden pole structures, than with hightension steel towers, but it can arise in both instances. When live conductors already extend between the poles a problem is presented in safely mounting each traveller on its respective pole. It is not normally convenient to shut down the existing lines, so that it becomes necessary to provide protection for the personnel involved. For example, when it is desired to place a traveller on say the upper cross-arm of a pole on which live conductors are already strung from a lower cross-arm, elaborate precautions have to be taken to protect the linesman. It is possible to use a boom truck, the boom of which is arranged to extend over the top of the existing lines. Alternatively it is common practice to install heavy fibreglass guards over each phase of the existing line, so that the linesman can climb through the fibreglass guards to the upper cross-arm to install the traveller. A great deal of time is consumed in applying and subsequently removing such fibreglass guards, but the available alternative (a boom truck) is expensive.

The principal object of the present invention is to provide an improved construction of traveller assembly adapted for mounting on the cross-arm of a transmission pole by manipulation from the ground or other location (e.g. half way up the pole) sufficiently remote from danger from existing live conductors.

One manner in which the invention may be carried into practice is illustrated diagrammatically in the accompanying dravn'ngs. It is to be understood that these drawings and the accompanying description are furnished by way of example only, and not by way of limitation of the broad scope of the invention, which latter is defined in the appended claims.

In the drawings:

FIGURE 1 is a side view of a traveller constructed in accordance with the invention, shown in position immediately prior to installation on a transmission pole cross-arm, the section being taken on the line II in FIGURE 4;

FIGURE 2 is a fragment of FIGURE 1 showing the parts at a later stage in the operation;

FIGURE 3 is a view similar to FIGURE 2 showing the parts at yet a later stage; and

FIGURE 4 is a view on the line IV-IV in FIGURE 3.

The traveller comprises a frame 10 composed of a pair of side members 11 and 12 joined together at their lower ends by a pair of cross-members 13 and 14. The side members 11 and 12 support a shaft 15 on which three sheaves 16, 17 and 18 are pivotally mounted.

A support arm 20 extends slidingly through passages 21 and 22 in the frame members 13 and 14 respectively. At its extreme upper end the support arm 20 is forked, as shown at 20a and 20b in FIGURE 4. A pin 23 in this forked upper end of the arm 20 is pivotally connected to one end of a link 24, the other end of which bears a pin 25 engaging a pair of bent around, forked ends 26 of a clamp arm 27. The other end of arm 27 terminates in a downwardly projecting flange 28. A pin 30 projects laterally from the support arm 20 for engagement with undersurfaces of the clamp arm 27.

At its lower end, the support arm 20 terminates in a boss 31 internally threaded to receive a screw 32, the lower end of which terminates in a plate 33 conventionally employed for engagement by a hotstick 34. A hotstick is a tool commonly used by transmission line workers and comprises an elongated insulated pole by which equipment, such as switches, can be manipulated from a remote location. The manner of connecting the hotstick 34 to the plate 33 is conventional in equipment of this type and requires no detailed explanation.

When the traveller shown in FIGURE 1 is to be engaged over a typical cross-arm 40, the linesman will, as necessary, partially climb the pole on which the crossarm 40 is secured, while remaining a safe distance below any live conductors. An assistant will then pass him the hotstick 34 with the traveller attached, in the position shown in FIGURE 1. The linesman will then lift the traveller safely through the live conductors, bringing it into the position adjacent the cross-arm 40 shown in FIG- URE 1. During this operation, the entire weight of the upper part of the traveller acts down through the support arm 20 to be supported in turn by the hotstick 34. This action will have the effect of urging the arm 20 upwardly in relation to the frame 10 of the traveller, that is to the position shown in FIGURE 1, wherein it will be noted that the pin 30 bears on the underside of the clamp arm 27 to elevate it to the unclamped position shown.

The linesman then maneuvers the assembly in the direction indicated by the arrow in FIGURE 1, until it embraces the cross-arm 40, i.e. tthe latter occupies the dotted line position shown in this figure. A projecting ledge 41 of the frame member 13 now overlies and rests upon the upper face of the cross-arm 40, a vertical side face of which now bears against the frame member 14. The operator now permits the weight of the traveller to be assumed by the cross-arm 40, with the result that the support arm 20 moves downwardly, in the manner indicated in FIGURE 2. The link 24 accordingly moves downwardly and outwardly, and the pin 30 falls to allow the clamp arm 27 to take up the position shown in FIG- URE 2, that is with its flange 28 embracing the outer vertical edge of the cross-arm 40.

The next step is for the operator to partially loosen the hotstick 34 from the plate 33, which allows rotation to be transmitted between these two parts, and to turn the stick 34 until securing means in the form of a spiked screwpad 42 on the upper end of the screw 32 has been firmly engaged with the under surface of the cross-arm 40, in the manner indicated in FIGURE 3. As the screw 32 is tightened, two effects are produce-d; firstly, the traveller is firmly secured to the cross-arm 40 in the vertical direction (by virtue of the diminution of the distance between the pad 42 and the ledge 41); at the same time, the resulttraveller is firmly secured to the cross-arm 40 both horizontally and vertically. With the traveller so secured, the

linesman can completely free the hotstick 34' from the plate 33, and the operation is complete. Removal of the traveller follows a reverse series of steps.

Projections 43 extend rearwardly from the frame member 13 to overlie the ends of the pin 25, which project laterally of the clamp arm 27. These projections 43 serve to confine the lower end of the link 24 and consequently the end 26 of the clamp arm 27 to movement substantially between the positions shown in FIGURES 1 and 3.

We claim:

1. A traveller assembly comprising:

i (a) a frame including members for supporting at least one sheave, and surfaces for overlying an upper face and for engaging a first vertical face of a horizontal cross-arm,

(b) a support arm slidable in. said frame between a lower and an upper location,

(c) a clamp arm including a flange for engaging the other vertical face of the cross-arm, said clamp arm being movable between an unclamped position in which said flange is withdrawn to allow the assembly to be placed over the cross-arm, and a clamping position in which said flange embraces the cross-arm, (d)'means connecting the clamp arm to the support arm and means locating the clamp arm in relation to the frame whereby movement of the support arm towards its upper location urges the clamp arm to unclamped position and movement of the support arm towards its lower location urges the clamp arm to clamping position,

(e) and securing means for movement to engage the undersurface of said cross-arm for clamping the same between said securing means and said overlying frame surface.

2. A traveller assembly according to claim 1, wherein said securing means is mounted on said support arm whereby clamping movement of said securing means urges said'support arm :more downwardly and thereby urges said clamp arm more tightly into clamping position.

3. A traveller assemby comprising:

(a) a frame including upstanding members for supporting at least one sheave, a horizontally extending ledge for overlying and engaging an upper face of a horizontal cross-arm and at least one vertical surface for engaging a first vertical 'face of the cross-arm,

(b) a support arm vertically slidable in said frame be tween a lower and an upper position, (c) a clamp arm for overlying said cross-arm, said clamp arm including 21 depending flange for engaging the other vertical face of the cross-arm, said clamp arm being pivotable between an upper, unclamped position in which said flange is above the cross-arm to allow the assembly to be placed thereover, and a lower clamping position in which said flange embraces said other vertical face of the crossarm,

(d) a link pivotally interconnecting the upper end of the support arm with the end of the clamp arm remote from said flange;

(e) anelement projecting from said support arm to engage the underside of said clamp arm and an element projecting from said end of the clamp arm to engage the frame whereby movement of said support arm to its upper location urges. the clamp arm upwardly to unclamped position and movement of the support arm towards its lower location permits said clamp arm to fall to clamping position, (f) and securing means mounted on said support arm for upward movement to engage the undersurface. of the cross-arm for clamping the same between the securing means andsaid ledge and for urging'said support arm downwardly whereby, through said link, to urge said flange tightly against said other vertical face of the cross-arm.

References Cited by the Examiner UNITED STATES PATENTS 121,583 12/1871 Campbell 248226 831,629 9/ 1906 Rollman 248226 1,069,000 7/ 1913 Giles 248226 X 2,202,184 5/1940 Berger. 2,220,214 11/ 1940 Cloutier 248-226 X 2,256,409 9/ 1941 Pucci 248226 SAMUEL F. COLEMAN, Primary Examiner. 

1. A TRAVELLER ASSEMBLY COMPRISING: (A) A FRAME INCLUDING MEMBERS FOR SUPPORTING AT LEAST ONE SHEAVE, AND SURFACES OF OVERLYING AN UPPER FACE AND FOR ENGAGING A FIRST VERTICAL FRAME OF A HORIZONTAL CROSS-ARM, (B) A SUPPORT ARM SLIDABLE IN SAID FRAME BETWEEN A LOWER AND AN UPPER LOCATION, (C) A CLAMP ARM INCLUDING A FLANGE FOR ENGAGING THE OTHER VERTICAL FACE OF THE CROSS-ARM, SAID CLAMP ARM BEING MOVABLE BETWEEN AN UNCLAMPED POSITION IN WHICH SAID FLANGE IS WITHDRAWN TO ALLOW THE ASSEMBLY TO BE PLACED OVER THE CROSS-ARM, AND A CLAMPING POSITION IN WHICH SAID FLANGE EMBRACES THE CROSS-ARM, (D) MEANS CONNECTING THE CLAMP ARM TO THE SUPPORT ARM AND MEANS LOCATING THE CLAMP ARM IN RELATION TO THE FRAME WHEREBY MOVEMENT OF THE SUPPORT ARM TOWARDS ITS UPPER LOCATION URGES THE CLAMP ARM TO UNCLAMPED POSITION AND MOVEMENT OF THE SUPPORT ARM TOWARDS ITS LOWER LOCATION URGES THE CLAMP ARM TO CLAMPING POSITION, (E) AND SECURING MEANS FOR MOVEMENT TO ENGAGE THE UNDERSURFACE OF SAID CROSS-ARM FOR CLAMPING THE SAME BETWEEN SAID SECURING MEANS AND SAID OVERLYING FRAME SURFACE. 